Present day:
The noonday sun shone gently down across the Everfree forest, casting away the shadows that clung on wherever the could. In a small clearing deep within the forest, a large crystal spire rose into the air. The pale blue crystal gleamed with the light of the sun. But something dark was swirling within. Twisted veins of blackness began to expand from the crystals heart, converging again near the base. A soft black light emanated from the point where the veins converged. The black light, or anti-light rather, began to grow in intensity. As the light expanded there was a loud snap as the crystal cracked. Several loud pops and bangs reverberated through the still woods as more and more fissures raced up the crystal spire. Finally, with a loud bang the spire shattered into several hundred pieces, which blew out across the clearing.
A smaller dome of crystal sat where the large spire once lay. The once white crystal had turned a dark purple, and it too was cracking. Considerably less spectacular than the spire, the crystal dome slowly disintegrated.
An indigo colored colt lay unconscious where the crystals had been. The unicorn breathed at a steady pace and simply lay still for several moments. The stallion grimaced, still unconscious, as his coat began to softly glow. A semiliquid mass seemed to seep from within the unicorn as his horn began to glow as well. As more of the dark magic left, the unicorn underwent a noticeable physical change.
The colts coat became a slightly lighter shade as the black tinge of it disappeared. His mane and tail softened in both their feel and color, and his teeth lost their pointedness. The most noticeable change was his eyes, even though they were currently closed. His eyes before had been like that of a dragon. Or Nightmare Moon. The unicorns pupil reverted back to it's oval shape, the whites of his eyes returned, and his irises went from a pale turquoise to their natural navy blue color. After a while the glow faded and the unicorn resumed his peaceful semi-sleep.
. . .
Indigo woke with a groan and shakily got to his hooves. Where in the name of Celestia was he? He looked up at the sky and judged it to be around noon. God his head ached. Indigo brought a hoof to his forehead and shook his head, trying to clear away the fogginess. How had he gotten here? The last thing he remembered was conversing with Luna about something. Though what that something was escaped him. With a jolt Indigo realized his memories had been altered. He could tell from the blurriness of most of his recent memories and the fact that they just felt...wrong. Indigo frowned and closed his eyes as he focused. His horn glowed with a dark purple light as he cast a spell to restore his memory. The spell fell disgustingly short. Indigo gasped as his legs wobbled and almost gave out underneath him. Who, or what, ever had manipulated his mind had been very thorough. He was sure that none of the spells he could do would be sufficient. He needed to find somepony with magic stronger than his to perform the spell. Problem was he had no idea where he was or how he got here. Or how to get out. A loud snap caused Indigo's ears to shoot up as he whipped his head around. In the pushes several meters away was a pair of glowing eyes. Without hesitation Indigo shot a blast of magic into the bush and took off in the other direction. Oh this would not be fun at all.